Disposable medical device introduction system

ABSTRACT

A disposable medical introduction system including a medical device and a disposable inserter. The disposable inserter includes a carrier to receive the medical device. The carrier includes at least one annular projection. The disposable inserter includes a retractor received within the at least one annular projection and movable relative to the at least one annular projection. The retractor has at least one retaining arm. The disposable inserter includes a needle cartridge coupled to the retractor that includes an insertion needle. The at least one retaining arm cooperates with the needle cartridge to maintain the insertion needle in a first, extended state. A movement of the retractor relative to the at least one annular projection releases the at least one retaining arm to move the insertion needle from the first, extended state to a second, retracted state.

TECHNICAL FIELD

The present technology is generally related to medical devices, such asa disposable medical device introduction system for use with a medicaldevice associated with a user, such as a physiological characteristicsensor or an infusion unit. More particularly, embodiments of thesubject matter relate to a disposable medical device introduction systemfor a physiological characteristic sensor or an infusion unit, and adisposable inserter for coupling the physiological characteristic sensoror the infusion unit to a user.

BACKGROUND

Sensors may be employed in the treatment of or monitoring of variousmedical conditions. Thin film electrochemical sensors are used to testanalyte levels in patients or users. More specifically, thin filmsensors have been designed for use in obtaining an indication of bloodglucose (BG) levels and monitoring BG levels in a diabetic user, withthe distal segment portion of the sensor positioned subcutaneously indirect contact with extracellular fluid. Such readings can be especiallyuseful in adjusting a treatment regimen which typically includes regularadministration of insulin to the user. A glucose sensor of the typedescribed above may be packaged and sold as a product, such as acontinuous glucose monitor, which is adhered to the patient during usevia an adhesive skin patch.

In addition, certain diseases or conditions may be treated, according tomodern medical techniques, by delivering a medication or other substanceto the body of a user, either in a continuous manner or at particulartimes or time intervals within an overall time period. For example,diabetes is commonly treated by delivering defined amounts of insulin tothe user at appropriate times. Some common modes of providing insulintherapy to a user include delivery of insulin through manually operatedsyringes and insulin pens. Other modern systems employ programmablefluid infusion devices (e.g., insulin pumps) to deliver controlledamounts of insulin to a user. In certain instances, these fluid infusiondevices require an insertion set, such as an infusion set that includesan infusion unit, to be coupled to the body of a user for the deliveryof the insulin. Generally, the infusion set is coupled to the fluidinfusion device via hollow tubing, which provides a fluid flow path fromthe fluid infusion device to the user via the infusion unit. Typically,the infusion unit requires a portion of a cannula, for example, to beinserted under the skin of the user to deliver the controlled amounts ofinsulin from the fluid infusion device to the user via the infusionunit.

In order to insert the glucose sensor into the user or to insert thecannula into the user, an inserter may be used, which includes a needleto puncture the skin of the user at the same time the glucose sensor orthe cannula is introduced. As the inserter employs the use of a needle,the inserter is unable to be conveniently disposed of, and rather, mustbe disposed of in a biohazard and/or sharps container or shipped to amedical supplier for proper disposal.

Accordingly, it is desirable to provide a disposable medical deviceintroduction system, which includes a disposable inserter for coupling aphysiological characteristic sensor, such as a continuous glucosemonitor, or an infusion unit, to an anatomy of a user. Furthermore,other desirable features and characteristics will become apparent fromthe subsequent detailed description and the appended claims, taken inconjunction with the accompanying drawings and the foregoing technicalfield and background.

BRIEF SUMMARY

The subject matter of this disclosure generally relates to a disposablemedical device introduction system that includes a disposable inserterfor coupling a medical device, such as a physiological characteristicsensor, for example, a continuous glucose sensor, or an infusion unit,to a user.

According to various embodiments, provided is a disposable inserter fora medical device. The disposable inserter includes a carrier to receivethe medical device. The carrier includes at least one annularprojection. The disposable inserter includes a retractor received withinthe at least one annular projection and movable relative to the at leastone annular projection. The retractor has at least one retaining arm.The disposable inserter includes a needle cartridge coupled to theretractor that includes an insertion needle. The at least one retainingarm cooperates with the needle cartridge to maintain the insertionneedle in a first, extended state. A movement of the retractor relativeto the at least one annular projection releases the at least oneretaining arm to move the insertion needle from the first, extendedstate to a second, retracted state.

Also provided according to various embodiments is a disposable medicaldevice introduction system. The disposable medical device introductionsystem includes a medical device, and a disposable inserter. Thedisposable inserter includes a plunger defining an access openingenclosed by a removable access cover, and a carrier to receive themedical device. The carrier includes at least one annular projection,and the carrier is movable relative to the plunger. The disposableinserter includes a retractor received within the at least one annularprojection and movable relative to the at least one annular projection.The retractor has at least one retaining arm. The disposable inserterincludes a needle cartridge coupled to the retractor that includes aninsertion needle. The at least one retaining arm cooperates with theneedle cartridge to maintain the insertion needle in a first, extendedstate, and a movement of the retractor relative to the at least oneannular projection releases the at least one retaining arm to move theinsertion needle from the first, extended state to a second, retractedstate. The needle cartridge is removable through the access opening.

The details of one or more aspects of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the techniques described in this disclosurewill be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the subject matter may be derived byreferring to the detailed description and claims when considered inconjunction with the following figures, wherein like reference numbersrefer to similar elements throughout the figures.

FIG. 1 is a perspective view of a disposable medical device introductionsystem that includes a disposable inserter for coupling a medicaldevice, in this example, a physiological characteristic sensor, to ananatomy of a user in accordance with various embodiments;

FIG. 2 is a cross-section view of the disposable medical deviceintroduction system of FIG. 1, taken along line 2-2 of FIG. 1, whichillustrates the disposable inserter in a first position and an insertionneedle associated with a needle cartridge of the disposable inserter ina first, extended state;

FIG. 3 is a partially exploded view of the disposable inserter of FIG.2;

FIG. 4 is a partially exploded view of the needle cartridge of FIG. 2;

FIG. 5 is a front view of the needle cartridge of FIG. 2;

FIG. 6 is a front view of the needle cartridge of FIG. 2, whichillustrates in phantom an insertion needle associated with the needlecartridge in a second, retracted state;

FIG. 7 is a front view of the needle cartridge of FIG. 2, whichillustrates in phantom the insertion needle associated with the needlecartridge in the first, extended state;

FIG. 8 is a cross-sectional view of the needle cartridge of FIG. 5,taken along line 8-8 of FIG. 5;

FIG. 9 is a cross-sectional view of the needle cartridge of FIG. 5,taken along line 9-9 of FIG. 5;

FIG. 10 is a perspective view of the disposable inserter in a thirdposition, in which the needle cartridge is removed from the disposableinserter;

FIG. 11 is a front view of a retractor and a retraction spring coupledto the needle cartridge of FIG. 2;

FIG. 12 is a cross-sectional view of the retractor, the retractionspring and the needle cartridge of FIG. 11, taken along line 12-12 ofFIG. 11;

FIG. 13 is a cross-sectional view of the retractor, the retractionspring and the needle cartridge of FIG. 11, taken along line 13-13 ofFIG. 11;

FIG. 14 is a cross-section view of the disposable medical deviceintroduction system of FIG. 1, taken from the perspective of line 2-2 ofFIG. 1, which illustrates the disposable inserter in a second positionand the insertion needle associated with the needle cartridge of thedisposable inserter in the first, extended state;

FIG. 15 is a cross-section view of the disposable medical deviceintroduction system of FIG. 1, taken from the perspective of line 2-2 ofFIG. 1, which illustrates the disposable inserter between the secondposition and a third position, the insertion needle associated with theneedle cartridge of the disposable inserter in the second, retractedstate and the physiological characteristic sensor is deployed on theuser;

FIG. 16 is a perspective view of the disposable inserter of FIG. 15, inwhich the disposable inserter is between the second position and thethird position, and the needle cartridge, with the insertion needle inthe second, retracted state, is graspable for removal from thedisposable inserter;

FIG. 17 is a cross-section view of the disposable medical deviceintroduction system of FIG. 1, taken from the perspective of line 2-2 ofFIG. 1, which illustrates the disposable inserter in the third position,the needle cartridge, with the insertion needle in the second, retractedstate, removed from the disposable inserter and the physiologicalcharacteristic sensor is deployed on the user;

FIG. 18 is a cross-section view of another exemplary disposable medicaldevice introduction system, taken from the perspective of line 2-2 ofFIG. 1, which illustrates a disposable inserter in a second position andthe insertion needle associated with the needle cartridge of thedisposable inserter in the first, extended state for deploying a portionof an infusion unit assembly onto an anatomy;

FIG. 19 is an exploded view of the infusion unit assembly for use withthe disposable inserter of FIG. 18 in accordance with variousembodiments;

FIG. 20 is a schematic illustration of the infusion unit assemblydeployed on the anatomy to define a fluid flow path to a user;

FIG. 21 is a cross-section view of another exemplary disposable medicaldevice introduction system, taken from the perspective of line 2-2 ofFIG. 1, which illustrates a disposable inserter in a second position andthe insertion needle associated with the needle cartridge of thedisposable inserter in the first, extended state for deploying aninfusion unit onto an anatomy;

FIG. 22 is a top view of the infusion unit for use with the disposableinserter of FIG. 21 in accordance with various embodiments; and

FIG. 23 is a schematic illustration of the infusion unit deployed on theanatomy to define a fluid flow path to a user.

DETAILED DESCRIPTION

The following detailed description is merely illustrative in nature andis not intended to limit the embodiments of the subject matter or theapplication and uses of such embodiments. As used herein, the word“exemplary” means “serving as an example, instance, or illustration.”Any implementation described herein as exemplary is not necessarily tobe construed as preferred or advantageous over other implementations.Furthermore, there is no intention to be bound by any expressed orimplied theory presented in the preceding technical field, background,brief summary or the following detailed description.

As used herein, the term “axial” refers to a direction that is generallyparallel to or coincident with an axis of rotation, axis of symmetry, orcenterline of a component or components. For example, in a cylinder ordisc with a centerline and generally circular ends or opposing faces,the “axial” direction may refer to the direction that generally extendsin parallel to the centerline between the opposite ends or faces. Incertain instances, the term “axial” may be utilized with respect tocomponents that are not cylindrical (or otherwise radially symmetric).For example, the “axial” direction for a rectangular housing containinga rotating shaft may be viewed as a direction that is generally parallelto or coincident with the rotational axis of the shaft. Furthermore, theterm “radially” as used herein may refer to a direction or arelationship of components with respect to a line extending outward froma shared centerline, axis, or similar reference, for example in a planeof a cylinder or disc that is perpendicular to the centerline or axis.In certain instances, components may be viewed as “radially” alignedeven though one or both of the components may not be cylindrical (orotherwise radially symmetric). Furthermore, the terms “axial” and“radial” (and any derivatives) may encompass directional relationshipsthat are other than precisely aligned with (e.g., oblique to) the trueaxial and radial dimensions, provided the relationship is predominantlyin the respective nominal axial or radial direction. As used herein, theterm “transverse” denotes an axis that crosses another axis at an anglesuch that the axis and the other axis are neither substantiallyperpendicular nor substantially parallel.

The following description relates to various embodiments of a disposablemedical device introduction system, which includes a physiologicalcharacteristic sensor or an infusion unit, and a disposable inserter.The systems described herein enable the disposable inserter to berecycled or disposed of in the user's own home (or current location)without requiring a disposal in a biohazard and/or sharps container oncethe physiological characteristic sensor or infusion unit is coupled tothe user. It should be noted that while the physiological characteristicsensor is described herein as being a continuous glucose monitor, itwill be understood that the physiological characteristic sensor maycomprise a variety of other sensors, such as cardiac monitors, bodytemperature sensors, EKG monitors etc., medical devices, and/or othercomponents that are intended to be affixed to the body of a user. Inaddition, the fluid infusion device for use with the infusion unit ofthe infusion set may be used for infusing fluid into the body of a user.In certain embodiments, the infused medication fluid is insulin. Inalternative embodiments, however, many other fluids may be administeredthrough infusion such as, but not limited to, disease treatments, drugsto treat pulmonary hypertension, iron chelation drugs, pain medications,anti-cancer treatments, medications, vitamins, hormones, or the like.For the sake of brevity, conventional features and characteristicsrelated to infusion system operation, insulin pump and/or infusion setoperation, fluid reservoirs, and fluid syringes may not be described indetail here. Examples of infusion pumps and/or related pump drivesystems used to administer insulin and other medications may be of thetype described in, but not limited to: U.S. Patent Publication Nos.2009/0299290 and 2008/0269687; U.S. Pat. Nos. 4,562,751; 4,678,408;4,685,903; 5,080,653; 5,505,709; 5,097,122; 6,485,465; 6,554,798;6,558,351; 6,659,980; 6,752,787; 6,817,990; 6,932,584; 7,621,893;7,828,764; and 7,905,868; which are each incorporated by referenceherein. Thus, while the non-limiting examples described below relate toa medical device used to treat diabetes (more specifically, a continuousglucose monitor or infusion unit associated with an infusion set),embodiments of the disclosed subject matter are not so limited.

Generally, the glucose sensor employed with the adhesive patch is acontinuous glucose sensor of the type used by diabetic users. For thesake of brevity, conventional aspects and technology related to glucosesensors and glucose sensor fabrication may not be described in detailhere. In this regard, examples of glucose sensors and theirmanufacturing may be of the type described in, but not limited to: U.S.Pat. Nos. 6,892,085, 7,468,033 and 9,295,786; and United States patentapplication number 2009/0299301 (which are each incorporated byreference herein). In addition, for the sake of brevity, conventionalaspects and technology related to sensor inserters may not be describedin detail here. In this regard, examples of sensor inserters may be ofthe type described in, but not limited to: U.S. Pat. No. 10,413,183 andU.S. application Ser. No. 16/892,854 filed on Jun. 4, 2020 (which areeach incorporated by reference herein).

With reference to FIG. 1, FIG. 1 is a perspective view of a disposablemedical device introduction system 100. In the example of FIG. 1, thedisposable medical device introduction system 100 includes aphysiological characteristic sensor assembly 102 and a disposableinserter 104. Generally, with reference to FIG. 2, the components of thephysiological characteristic sensor assembly 102 are coupled together asa single unit. The physiological characteristic sensor assembly 102 andthe disposable inserter 104 may be packaged together for use by aconsumer or user. The disposable inserter 104 is in a first position inFIG. 2.

The physiological characteristic sensor assembly 102 may comprise anysuitable physiological characteristic sensor, such as a continuousglucose monitor, for use with the disposable inserter 104, and thus, thephysiological characteristic sensor assembly 102 will not be discussedin great detail herein. Briefly, the physiological characteristic sensorassembly 102 includes a physiological characteristic sensor 106 and anadhesive skin patch or adhesive patch 108. The physiologicalcharacteristic sensor 106 includes a sensor electronics module (notshown), such as a wireless transmitter that communicates with a fluidinfusion device (such as an infusion pump), a monitor device, or thelike, which connects to the physiological characteristic sensor 106after the insertion or deployment of a portion of the physiologicalcharacteristic sensor 106 in the body of the user. In certainembodiments, the physiological characteristic sensor 106 includes aglucose sensor 110 and a sensor housing 112. It should be noted that thephysiological characteristic sensor 106 is not limited to a glucosesensor, but rather, various other physiological characteristic sensorsmay be employed. The glucose sensor 110 may be provided as an integralpart of the sensor housing 112. The sensor housing 112 gives structuralsupport to the glucose sensor 110, and facilitates entry of the glucosesensor 110 into the body of the user. The glucose sensor 110 is anelectrochemical sensor that includes the glucose oxidase enzyme, as iswell understood by those familiar with glucose sensor technology. Theglucose oxidase enzyme enables the glucose sensor 110 to monitor bloodglucose levels in a diabetic patient or user by effecting a reaction ofglucose and oxygen. Again, although certain embodiments pertain toglucose sensors, the technology described here can be adapted for usewith any one of the wide variety of sensors known in the art. Generally,the glucose sensor 110 is positionable in subcutaneous tissue of theuser by an insertion needle 162 of the disposable inserter 104 tomeasure the glucose oxidase enzyme.

The sensor housing 112 is coupled to the disposable inserter 104 and iscoupled to the adhesive patch 108. The sensor housing 112 may alsofeature electrical and physical interfaces and elements that accommodatethe sensor electronics module, such as the wireless transmitter thatcommunicates with the infusion pump, the monitor device, or the like. Incertain embodiments, the sensor housing 112 is composed at least in partfrom a plastic material. For the embodiment described here, the bulk ofthe sensor housing 112 is formed as a molded plastic component. Thesensor housing 112 may be formed from acrylonitrile butadiene styrene,nylon, an acrylonitrile butadiene styrene polycarbonate blend, polyvinylchloride, polytetrafluoroethylene (PTFE), polypropylene, polyether etherketone (PEEK), polycarbonate or the like.

The adhesive patch 108 is coupled to the sensor housing 112 and affixesthe sensor housing 112, and thus, the glucose sensor 110, to an anatomy,such as the skin of the user. The adhesive patch 108 is contained withinthe disposable inserter 104 during packaging and shipping. The adhesivepatch 108 may be composed of a flexible and breathable material with oneor more adhesive layers, such as cloth, a bandage-like material, and thelike. For example, suitable materials could include polyurethane,polyethylene, polyester, polypropylene, polytetrafluoroethylene (PTFE),or other polymers, to which one or more adhesive layers are applied.

With reference back to FIG. 2, in various embodiments, the physiologicalcharacteristic sensor assembly 102 is coupled to the disposable inserter104 for shipping and delivering the physiological characteristic sensorassembly 102 to the user. The disposable inserter 104 is manipulatableby a user to couple the glucose sensor 110 and the physiologicalcharacteristic sensor 106 to the user. With additional reference to FIG.3, the disposable inserter 104 includes a needle cartridge 120, aplunger 122, a first biasing member or insertion spring 124, a frame126, a retractor 128, a second biasing member or retraction spring 130,a retainer 132, a carrier 134, a magnet 136 and a cap 138. In thisexample, the cap 138 includes a membrane 140, as will be discussedfurther herein.

The needle cartridge 120 is movable relative to the plunger 122 toinsert the glucose sensor 110 into the anatomy. With reference to FIG.4, the needle cartridge 120 includes a needle inserter 150, a thirdbiasing member or third spring 152 and a cartridge housing 154. Theneedle inserter 150 includes a needle carrier 160 and an insertionneedle 162. The needle carrier 160 is overmolded onto the insertionneedle 162. The needle carrier 160 is substantially cylindrical. Theneedle carrier 160 includes a first carrier end 164 opposite a secondcarrier end 166 and defines a cross-bore 168. The first carrier end 164includes at least one contact surface, and in this example, includesopposed contact surfaces defined as chamfered surfaces 170. Thechamfered surfaces 170 define a first contact surface for the cartridgehousing 154, as will be discussed. Generally, the chamfered surfaces 170are defined on opposed sides of the needle carrier 160, however, thechamfered surfaces 170 may comprise a single surface defined about aperimeter of the first carrier end 164, if desired. The second carrierend 166 is coupled to the insertion needle 162. The second carrier end166 may include a collar 172 that extends outward from the secondcarrier end 166 and surrounds a portion of the insertion needle 162. Thecollar 172 is a spring guide for the third spring 152. The cross-bore168 is defined through the needle carrier 160 from a first side to asecond side to as to extend along an axis that is transverse or obliqueto an axis defined by the insertion needle 162. The cross-bore 168provides for ease of manufacturing by enabling the needle carrier 160 tobe molded onto the insertion needle 162. The insertion needle 162 isgenerally a stainless steel needle, which extends for a distance beyonda distal end of the glucose sensor 110 to couple the glucose sensor 110to the anatomy (FIG. 2).

The third spring 152 may be a helical coil spring, which is composed ofa suitable biocompatible material, such as a spring steel that is woundto form the third spring 152. The third spring 152 is received betweenthe needle carrier 160 and a second cartridge end 174 of the cartridgehousing 154 (FIG. 5). The third spring 152 is held in compression by theneedle carrier 160 to maintain the insertion needle 162 in a firstextended state (shown in FIG. 5), and once released by the needlecarrier 160, expands to move the needle carrier 160 relative to thecartridge housing 154 and within the cartridge housing 154, therebymoving the insertion needle 162 to a second retracted state (shown inFIG. 6) for disposal, as will be discussed further herein.

With reference to FIG. 4, the cartridge housing 154 is substantiallycylindrical, and extends along a cartridge longitudinal axis CL. Thecartridge longitudinal axis CL is parallel to a longitudinal axis L ofthe disposable inserter 104 (FIG. 2). The cartridge housing 154 iscomposed of a suitable polymer based material, including, but notlimited to acrylonitrile butadiene styrene, nylon, an acrylonitrilebutadiene styrene polycarbonate blend, polyvinyl chloride,polytetrafluoroethylene (PTFE), polypropylene, polyether ether ketone(PEEK), polycarbonate or the like. The cartridge housing 154 includes acap 175, a first cartridge end 176 opposite the second cartridge end174, a cartridge body 177 that interconnects the first cartridge end 176with the second cartridge end 174, at least one lock arm 178 and atleast one coupling tab 180. The cartridge housing 154 also defines acartridge bore 182 that extends through the cartridge body 177 from thefirst cartridge end 176 to the second cartridge end 174.

The cap 175 is coupled to the cartridge body 177 at the first cartridgeend 176 to enclose the cartridge bore 182 (FIG. 6). The cap 175 isgenerally discretely formed from the cartridge body 177, and is coupledto the first cartridge end 176 via ultrasonic welding, adhesives, etc.The cap 175 provides a stop for a travel of the needle carrier 160within the cartridge bore 182 (FIG. 6). In this regard, the cap 175includes a first exterior surface 184 opposite a second interior surface186. The first exterior surface 184 is substantially planar or flat. Thesecond interior surface 186 is defined along a cap projection 175 a thatextends into the cartridge bore 182 to enclose the cartridge bore 182(FIG. 9). The second interior surface 186 provides a stop surface forfurther advancement of the needle carrier 160 within the cartridge bore182. The second cartridge end 174 includes a third interior surface 188opposite a fourth exterior surface 190, and defines a bore 192 thatextends through the third interior surface 188 and the fourth exteriorsurface 190. The third interior surface 188 provides a seat for thethird spring 152, and includes a guide collar 189. The guide collar 189serves to guide a movement of the third spring 152. The fourth exteriorsurface 190 is substantially planar or flat. The bore 192 is definedthrough the third interior surface 188 and the fourth exterior surface190 to enable the insertion needle 162 to pass through the bore 192 intothe cartridge bore 182 when the insertion needle 162 is in the second,retracted state (shown in FIG. 6).

The cartridge body 177 is substantially cylindrical, and interconnectsthe first cartridge end 176 with the second cartridge end 174. The atleast one lock arm 178 and the at least one coupling tab 180 areintegrally formed with the cartridge housing 154. In certainembodiments, each of the at least one lock arm 178 and the at least onecoupling tab 180 are integrally formed with the cartridge body 177. Withreference to FIG. 8, the at least one lock arm 178 includes two lockarms 178 a, 178 b. The lock arms 178 a, 178 b extend from the firstcartridge end 176 toward the second cartridge end 174. The lock arms 178a, 178 b are opposed from each other about a perimeter or circumferenceof the cartridge body 177. Each of the lock arms 178 a, 178 b include afirst lock arm end 194 and a second lock arm end 196 interconnected byan arm 198. Each of the lock arms 178 a, 178 b are cantilevered relativeto the cartridge body 177, and thus, recesses 179 a, 179 b may bedefined about the second lock arm end 196 and the arm 198 to enable thesecond lock arm end 196 to move relative to the cartridge body 177. Aswill be discussed, a movement of the lock arms 178 a, 178 b relative tothe cartridge body 177 results in a movement of the insertion needle 162from the first, extended state (FIG. 5) to the second, retracted state(FIG. 6).

The first lock arm end 194 is integrally formed with the cartridge body177, and extends along an axis parallel to the cartridge longitudinalaxis CL. The second lock arm end 196 has a bulbous portion 200, whichdefines a first contact surface 202 and a second contact surface 204.The first contact surface 202 is defined so as to extend a distancebeyond an exterior surface 177 a of the cartridge body 177 when theinsertion needle 162 is in the first extended state (FIG. 8) to contacta portion of the retractor 128. In certain embodiments, the firstcontact surface 202 is a flat angled surface, which is defined along anexterior surface 196 a of the second lock arm end 196. It should benoted that the first contact surface 202 may have other configurations,if desired. Generally, the first contact surface 202 is angled tocorrespond with an angle of the portion of the retractor 128 to providesurface to surface contact.

The second contact surface 204 is defined diagonally opposite from thefirst contact surface 202. The second contact surface 204 is defined soas to be positioned within the cartridge bore 182 to contact thechamfered surfaces 170 of the needle carrier 160 when the insertionneedle 162 is in the first extended state. In certain embodiments, thesecond contact surface 204 is a flat angled surface, which is definedalong an interior surface 196 b of the second lock arm end 196. Itshould be noted that the second contact surface 204 may have otherconfigurations, if desired. Generally, the first contact surface 202 andthe second contact surface 204 each extend along an axis, and the axesof the first contact surface 202 and the second contact surface 204 areparallel to each other and transverse or oblique to the cartridgelongitudinal axis CL. The second contact surface 204 is angled tocorrespond with the angle of the chamfered surfaces 170 to providesurface to surface contact between the respective one of the lock arms178 a, 178 b and the respective one of the chamfered surfaces 170. Thearm 198 interconnects the first lock arm end 194 and the second lock armend 196. The arm 198 is surrounded by the respective recess 179 a, 179 bsuch that the arm 198 is a cantilevered beam.

With reference to FIG. 9, the at least one coupling tab 180 includes twocoupling tabs 180 a, 180 b. The coupling tabs 180 a, 180 b are definedproximate the second cartridge end 174. The coupling tabs 180 a, 180 bare opposed from each other about a perimeter or circumference of thecartridge body 177. Each of the coupling tabs 180 a, 180 b include afirst tab end 206 and a second tab end 208 interconnected by a couplingarm 210. Each of the coupling tabs 180 a, 180 b are cantileveredrelative to the cartridge body 177, and thus, recesses 211 a, 211 b maybe defined about the second tab end 208 and the coupling arm 210 toenable the second tab end 208 to move relative to the cartridge body177. Generally, the recesses 211 a, 211 b are defined such that thesecond tab end 208 is spaced apart from the third interior surface 188of the second cartridge end 174. As will be discussed, a movement of thecoupling tabs 180 a, 180 b relative to the cartridge body 177 enables aremoval of the needle cartridge 120 from the plunger 122.

The first tab end 206 is integrally formed with the cartridge body 177,and extends along an axis parallel to the cartridge longitudinal axisCL. The second tab end 208 has an angled projection 212, which engageswith a portion of the retractor 128. The projection 212 is substantiallytriangular in shape, and is defined so as to extend a distance beyondthe exterior surface 177 a of the cartridge body 177 when the insertionneedle 162 is in the first, extended state (FIG. 8) to contact a portionof the retractor 128. The coupling arm 210 interconnects the first tabend 206 and the second tab end 208. The coupling arm 210 is surroundedby the respective recess 211 a, 211 b such that the coupling arm 210 isa cantilevered beam.

With reference back to FIG. 3, the plunger 122 is composed of abiocompatible polymer, and may be molded, cast, printed, etc. Theplunger 122 surrounds the frame 126, and includes a plurality of threads220 defined about a surface of the plunger 122 adjacent to a second,bottom end 122 b. The threads 220 removably couple the cap 138 to theplunger 122, as will be discussed. The plunger 122 is shaped tocorrespond to the shape of the physiological characteristic sensor 106(FIG. 2) so that the user intuitively knows the position and orientationof the physiological characteristic sensor 106 when the disposableinserter 104 is used to couple the physiological characteristic sensor106 to the anatomy. This enables the user to position the disposableinserter 104 at a location by feel, without having to see the insertionsite, such as a back of an arm, for example. In certain embodiments, afirst, top end 122 a of the plunger 122 defines an access opening 224and a removable cover or access cover 226, which enables a removal ofthe needle cartridge 120 from the disposable inserter 104.

With reference to FIG. 10, the access opening 224 is shown in greaterdetail. In FIG. 10, the access cover 226 is removed from the plunger 122and the needle cartridge 120 is shown removed from the disposableinserter 104 after a deployment of the physiological characteristicsensor 106 onto the anatomy. As shown, in this example, the accessopening 224 includes a central circular portion 227 and a pair ofopposed rectangular slots 229. The central circular portion 227 has adiameter D2 that is different than, and in this example, larger than, adiameter D1 of the cartridge body 177. The difference in the diametersD1, D2 enables the cartridge body 177 to pass through the access opening224. The opposed rectangular slots 229 are in communication with thecentral circular portion 227 to enable the coupling tabs 180 a, 180 b topass through the access opening 224. Generally, the coupling tabs 180 a,180 b extend beyond a perimeter or circumference of the cartridge body177 for a distance D3, which is different and less than a distance D4defined by the opposed rectangular slots 229. The distance D3 is alsodifferent, and greater than, the diameter D1 (FIG. 9). Thus, generally,the access opening 224 enables the removal of the needle cartridge 120from the disposable inserter 104. It should be noted that the accessopening 224 may be configured or shaped differently, if desired, basedon a shape of the needle cartridge 120.

The access opening 224 may be recessed relative to a surface 122 c ofthe plunger 122 at the first end 122 a so as to be disposed below aplane defined by the surface 122 c. In this example, a recess 228 isdefined at the first end 122 a to surround the access opening 224, andthe access opening 224 is defined through the recess 228. An inner rib230 is defined about the access opening 224 to form a channel 232between a sidewall of the recess 228 and the inner rib 230. The innerrib 230 is defined so as to be rectangular in this example, but theinner rib 230 may have any desired shape. The inner rib 230 extendsoutwardly from the recess 228 and is substantially coplanar with thesurface 122 c. The channel 232 is generally defined so as to berectangular and to substantially surround the access opening 224. Thechannel 232 receives an adhesive, for example, to couple the removableaccess cover 226 (FIG. 1) to the plunger 122. It should be noted that inthis example, the recess 228 also defines a recessed notch 234 that isspaced apart from the inner rib 230. The recessed notch 234 is spacedapart from the inner rib 230 to ensure that a minimal amount or noadhesive flows into the recessed notch 234. This ensures that a portionof the removable access cover 226 is unadhered to the plunger 122, whichenables a user to insert a finger into the recessed notch 234 to graspthe access cover 226 and peel the access cover 226 from the plunger 122.

With reference to FIG. 1, the access cover 226 is shown attached to theplunger 122. In this example, the access cover 226 is substantiallyrectangular and includes a pull-tab 226 a, however, the access cover 226may have any desired shape that corresponds with the needle cartridge120 and the access opening 224. The access cover 226 may be composed ofany suitable material, and in certain embodiments, the access cover 226is composed of a gas permeable polymeric material, such as Tyvek®manufactured by DuPont™ of Midland, Mich., which is coupled to theplunger 122 along the surface 122 c of the recess 228, via adhesives,ultrasonic welding, heat bond, etc., for example. The access opening 224is covered by the access cover 226. The access opening 224 cooperateswith the access cover 226 to enable the sterilization of thephysiological characteristic sensor 106 and the needle cartridge 120contained within the disposable inserter 104. Generally, a seal isformed by the access cover 226 about the access opening 224 and during asterilization procedure, the sterilization gas may penetrate into andout of the disposable inserter 104, via the access opening 224, andsterilize the physiological characteristic sensor 106 and an interior ofthe disposable inserter 104.

With reference back to FIG. 2, the plunger 122 also defines a firstinner guide surface 238 and a second inner guide surface 240. Each ofthe first inner guide surface 238 and the second inner guide surface 240extend inward from an inner surface of the plunger 122. In this example,each of the first inner guide surface 238 and the second inner guidesurface 240 extend from the first end 122 a toward the second end 122 b.In certain embodiments, the first inner guide surface 238 includes aslot that cooperates with a rail 242 defined within the retractor 128(FIG. 3). The engagement of the rail 242 with the slot guides theretractor 128 toward the first end 122 a of the plunger 122 tofacilitate the removal of the needle cartridge 120 after deployment ofthe physiological characteristic sensor 106. The second inner guidesurface 240 cooperates with the carrier 134 to guide the carrier 134during deployment of the physiological characteristic sensor 106. Theplunger 122 also includes a plurality of projections 244 that extendradially inward spaced apart about an interior periphery of the plunger122. The projections 244 cooperate with slots 246 defined in the frame126. Generally, the projections 244 and the slots 246 cooperate to aguide a movement of the plunger 122 relative to the frame 126. Theplunger 122 also includes frame projections 247. The frame projections247 extend radially inward and are defined about a perimeter of theplunger 122. As will be discussed, the frame projections 247 cooperatewith the frame 126 to release the physiological characteristic sensor106 when the disposable inserter 104 is in a second position.

The insertion spring 124 is a helical coil spring, which is composed ofa suitable biocompatible material, such as a spring steel that is woundto form the insertion spring 124. The insertion spring 124 is receivedbetween the second inner guide surface 240 of the plunger 122 and asurface 134 a of the carrier 134. Generally, the insertion spring 124expands as the carrier 134 moves toward a second, bottom end 126 b ofthe frame 126 to couple the physiological characteristic sensor 106 tothe user and exerts a spring force F1 along the longitudinal axis L tomove the carrier 134 toward the bottom end 134 b of the frame 126 fordeployment of the physiological characteristic sensor 106.

The frame 126 is received within the plunger 122. Generally, the frame126 extends a distance beyond the plunger 122. The frame 126 is composedof a biocompatible polymer, and may be molded, cast, printed, etc. Withreference to FIG. 3, the frame 126 includes a first frame portion 250and a second frame portion 252. The slots 246 are defined in the firstframe portion 250 and extend from a top surface 126 a of the frame 126to the second frame portion 252. The second frame portion 252 surroundsthe carrier 134 such that the physiological characteristic sensor 106(FIG. 2) is positioned within the second frame portion 252 of the frame126. With reference to FIG. 14, the second frame portion 252 includes atleast one or a plurality of ribs 254. The ribs 254 are spaced apartabout the inner perimeter of the frame 126, and extend for a distance toengage with the retainer 132 as shown. In a first position, as shown inFIG. 2, the ribs 254 engage with the retainer 132 to retain thephysiological characteristic sensor 106. In a second position, the ribs254 are released, via contact between the frame projections 247 of theplunger 122 and the ribs 254, which causes the retainer 132 to releasethe physiological characteristic sensor 106 for deployment onto theanatomy.

The retractor 128 is coupled to a second annular projection 256 of thecarrier 134. The retractor 128 is composed of a biocompatible polymer,and may be molded, cast, printed, etc. With reference to FIG. 11, theretractor 128 includes a first portion 260, a second portion 262 anddefines a bore 263 that extends through the first portion 260 and thesecond portion 262. The needle cartridge 120 is received within the bore263. The first portion 260 has a greater diameter than the secondportion 262. The first portion 260 includes one or more guideprojections 264, which are spaced apart about a perimeter of the firstportion 260. The guide projections 264 contact a second annularprojection 256 of the carrier 134. The first portion 260 may alsoinclude a locating projection 261, which assists with assembly of theretractor 128 to the carrier 134. The first portion 260 also includes atleast one retaining arm 266. With reference to FIG. 12, the retractor128 is shown coupled to the needle cartridge 120 and the retractionspring 130. In this example, the at least one retaining arm 266 includestwo retaining arms 266 a, 266 b. The retaining arms 266 a, 266 b extendfrom a first end 260 a toward a second end 260 b of the first portion260. Generally, the retaining arms 266 a, 266 b are defined so as to bespaced apart from the second portion 262 by a distance D5 so that theretaining arms 266 a, 266 b engage with the lock arms 178 a, 178 b. Theretaining arms 266 a, 266 b are opposed from each other about aperimeter or circumference of the first portion 260. Each of theretaining arms 266 a, 266 b include a first retaining arm end 268 and asecond retaining arm end 270 interconnected by an arm 272. Each of theretaining arms 266 a, 266 b are cantilevered relative to the firstportion 260, and thus, recesses 271 a, 271 b (FIG. 11) may be definedabout the second retaining arm end 270 and the arm 272 to enable thesecond retaining arm end 270 to move relative to the first portion 260of the retractor 128. As will be discussed, a movement of the retainingarms 266 a, 266 b relative to the first portion 260 of the retractor 128results in a movement of the insertion needle 162 from the first,extended state (FIG. 5) to the second, retracted state (FIG. 6).

The first retaining arm end 268 is integrally formed with the firstportion 260, and extends along an axis parallel to a retractorlongitudinal axis RL. The second retaining arm end 270 has a triangularportion 274, which defines a retaining contact surface 276. Thetriangular portion 274 extends inward into the bore 263 to contact thefirst contact surface 202 of the respective lock arm 178 a, 178 b whenthe insertion needle 162 is in the first extended state (FIG. 8). Incertain embodiments, the retaining contact surface 276 is a flat angledsurface, which is defined along one side of the triangular portion 274.Generally, the retaining contact surface 276 is angled to correspondwith the angle of the first contact surface 202 of the lock arms 178 a,178 b to provide surface to surface contact. It should be noted that theretaining contact surface 276 may have other configurations, if desired.Generally, the retaining contact surface 276 extends along an axis,which is transverse or oblique to the retainer longitudinal axis RL. Thearm 272 interconnects the first retaining arm end 268 and the secondretaining arm end 270. The arm 272 is surrounded by the respectiverecess 271 a, 271 b such that the arm 272 is a cantilevered beam.

The second portion 262 is coupled to the cartridge housing 154 of theneedle cartridge 120. The diameter of the second portion 262 is sizedsuch that the retraction spring 130 is positioned between the firstportion 260 and the carrier 134 so as to surround the second portion262, as shown in FIG. 2. With reference to FIG. 13, the second portion262 defines at least one internal slot or opposed internal slots 280.The internal slots 280 slidably receive the second tab end 208 of therespective coupling tabs 180 a, 180 b. The internal slots 280 include astop surface 280 a, which limits an advancement of the needle cartridge120 within the retractor 128. Generally, the internal slots 280 guidethe needle cartridge 120 during the deployment of the physiologicalcharacteristic sensor 106 (FIG. 2) into the anatomy. Once thephysiological characteristic sensor 106 (FIG. 2) is deployed, theinternal slots 280 enable the needle cartridge 120 to be removed oruncoupled from the retractor 128 as the internal slots 280 end at thefirst portion 260. As the first portion 260 has a greater diameter thanthe second portion 262, the second tab end 208 of the coupling tabs 180a, 180 b pass freely through the first portion 260 to enable the removalof the needle cartridge 120.

With reference to FIG. 2, the retraction spring 130 may be a helicalcoil spring, which is composed of a suitable biocompatible material,such as a spring steel that is wound to form the retraction spring 130.The retraction spring 130 is received between the second portion 262 ofthe retractor 128 and a surface 134 a of the carrier 134. Afterdeployment, the retraction spring 130 expands and exerts a spring forceF2 along the longitudinal axis L to move the retractor 128 toward thefirst inner guide surface 238 of the plunger 122 to enable the removalof the needle cartridge 120.

With reference to FIG. 2, the retainer 132 is coupled to and receivedabout a perimeter of the carrier 134. The retainer 132 assists incoupling or retaining the physiological characteristic sensor 106 on thecarrier 134. The retainer 132 may be composed of a biocompatiblepolymer, and may be molded, cast, printed, etc. The retainer 132 is thesame as the sensor retainer described in U.S. application Ser. No.16/892,854 filed on Jun. 4, 2020, previously incorporated herein byreference, and thus, the retainer 132 will be discussed briefly herein.Generally, the retainer 132 includes at least one or plurality ofretainer arms 282, which are spaced apart about a perimeter of theretainer 132. Each of the retainer arms 282 is cantilevered from theretainer 132, and includes a contact surface that retains thephysiological characteristic sensor 106 in a second state. In a firststate, the contact surface of the retainer arms 282 does not contact thephysiological characteristic sensor 106 such that the physiologicalcharacteristic sensor 106 is released or uncoupled from the retainer 132when the retainer arms 282 are in the first state. In the first state, agap is defined between a terminal end of each of the retainer arms 282and a surface of the retainer 132. In the second state, each of the ribs254 of the frame 126 contact a respective one of the retainer arms 282to bias or compress the retainer arms 282. In the second state, the gapis substantially eliminated and the terminal end of each of the retainerarms 282 contacts a surface of the retainer 132. In the second state,the contact surface is held against the physiological characteristicsensor 106 to retain the physiological characteristic sensor 106 on theretainer 132. Generally, the frame projections 247 of the plunger 122contact the ribs 254 of the frame 126, which pushes the ribs 254outward, thereby releasing the retainer arms 282. The release of theretainer arms 282 moves the retainer arms 282 from the second state tothe first state, which releases the contact surface from thephysiological characteristic sensor 106.

The carrier 134 moves relative to the frame 126 to deploy thephysiological characteristic sensor 106 onto the user. The carrier 134may be composed of a biocompatible polymer, and may be molded, cast,printed, etc. The carrier 134 includes a support body 290 and aretaining flange 292. The support body 290 is annular, and includes atleast one annular projection, and in this example, includes a firstannular projection 294 and the second annular projection 256 that areconcentric. The first annular projection 294 couples the carrier 134 tothe frame 126, and the second annular projection 256 couples theretractor 128 to the carrier 134. The second annular projection 256 mayalso include opposed slots 296 (FIG. 3), which cooperate with theretractor 128 to couple the retractor 128 to the carrier 134. In thisexample the second annular projection 256 extends for a distance D6 fromthe retaining flange 292. By extending the distance D6, the secondannular projection 256 applies a force to the retaining arms 266 a, 226b of the first portion 260 of the retractor 128. Stated another way, thedistance D6 ensures that a sidewall 256 a of the second annularprojection 256 applies a force to the retaining arms 266 a, 266 b, whichin turn, applies a force to the needle carrier 160 via the lock arms 178a, 178 b to maintain the insertion needle 162 in the first, extendedstate.

With reference to FIG. 3, the carrier 134 also includes insertion snaps298. The insertion snaps 298 extend outwardly from the first annularprojection 294, and are received within the slots 246 of the frame 126.Generally, the insertion snaps 298 are spaced apart from a surface ofthe slots 246 to inhibit a relative movement between the carrier 134 andthe frame 126. The cap 138 applies a force F3 to the physiologicalcharacteristic sensor 106 in the first position, which causes theinsertion snaps 298 of the carrier 134 to be spaced apart from thesurface of the frame 126 and free floating. This ensures that if thedisposable inserter 104 is accidentally mishandled in the firstposition, the carrier 134 is not inadvertently released.

With reference to FIG. 2, a ramp surface 300 defined interiorly withinthe plunger 122 contacts the insertion snaps 298 (FIG. 3) as the plunger122 moves relative to the frame 126. The contact between the rampsurface 300 and the insertion snaps 298 causes the insertion snaps 298(FIG. 3) to deflect, thereby releasing the insertion snaps 298 (FIG. 3)from the slots 246 and from the frame 126. The release of the carrier134 from the frame 126 enables the insertion spring 124 to apply theforce F1 to couple the physiological characteristic sensor 106 to theanatomy.

With reference to FIG. 3, the retaining flange 292 is substantiallyrectangular in shape, and is coupled to the retainer 132. The retainingflange 292 includes a plurality of retaining tabs 302 and defines acontact surface 304 (FIG. 2). The retaining tabs 302 couple the retainer132 to the carrier 134. With reference to FIG. 2, the contact surface304 is continuous and is defined about a perimeter of the retainingflange 292. The contact surface 304 presses the adhesive patch 108against the anatomy of the user upon deployment of the physiologicalcharacteristic sensor 106 to ensure that the adhesive patch 108 iscoupled to the user over an entirety of the adhesive patch 108.

In this example, the magnet 136 is coupled to the cap 138. The magnet136 comprises any suitable permanent magnet composed of a ferromagneticmaterial that is axially magnetized. As the magnet 136 and the cap 138are the same as the magnet 214 and the cap 216 discussed in U.S.application Ser. No. 16/892,854 filed on Jun. 4, 2020, previouslyincorporated herein, the magnet 136 and the cap 138 will be discussedbriefly herein. Generally, the magnet 136 is annular and cooperates withthe physiological characteristic sensor 106 to activate thephysiological characteristic sensor 106 based on a removal of the cap138. For example, the physiological characteristic sensor 106 mayinclude a magnetic field sensor that is responsive to the magnetic fieldgenerated by the magnet 136 to activate the physiological characteristicsensor 106 based on a change in the magnetic field. The cap 138 may becomposed of a biocompatible polymer, and may be molded, cast, printed,etc. The cap 138 includes a projection 310, a cap base 312 and asidewall 314. The projection 310 extends axially upward from the capbase 312 and defines an annular channel 310 a that is coupled to themagnet 136. The projection 310 terminates in a tip 316. The tip 316applies the force F3 against the physiological characteristic sensor106, which causes the insertion snaps 298 (FIG. 3) to float within theslots 246.

The cap base 312 has a first base surface 320 opposite a second basesurface 322 and defines a plurality of openings 324. The first basesurface 320 is coupled to or integrally formed with the projection 310.The second base surface 322 defines a circular recess 322 a, whichreceives the membrane 140. The membrane 140 is a gas permeable polymericmaterial, such as Tyvek® manufactured by DuPont™ of Midland, Mich.,which is coupled to the cap 138 along a surface of the circular recess322 a, via adhesives, heat bond, etc., for example. The openings 324 arecovered by the membrane 140. The openings 324 cooperate with themembrane 140 to enable the sterilization of the physiologicalcharacteristic sensor 106 contained within the disposable inserter 104.Generally, the plunger 122 and the cap 138 cooperate to form a seal,such that during a sterilization procedure, the sterilization gas maypenetrate into and out of the disposable inserter 104, via the openings324, and sterilize the physiological characteristic sensor 106 and aninterior of the disposable inserter 104. The second end 122 b of theplunger 122 is coupled to the cap 138 in an interference fit, whichinhibits fluids, such as air and liquids, to flow into the disposableinserter 104. In this example, the sidewall 314 of the cap 138 includesa lip 326, which circumscribes the cap 138 and receives the second end122 b of the plunger 122 with the interference fit. The cap base 312 mayalso include a frame receiving channel 328, which receives the secondend 126 b of the frame 126.

The sidewall 314 includes the lip 326, a plurality of threads 330 and aframe projection 332. The plurality of threads 330 are defined so as tobe spaced apart from the lip 326. The plurality of threads 330 engagewith the threads 220 of the plunger 122 to removably couple the cap 138to the plunger 122. The frame projection 332 cooperates with a thread126 c defined on the frame 126. The frame projection 332 acts as athread such that the cap 138 is screwed onto both the frame 126 and theplunger 122. By screwing the cap 138 onto both the frame 126 and theplunger 122, the frame 126 is locked in position relative to the plunger122, which inhibits the frame 126 from moving relative to the plunger122 in an instance where the disposable inserter 104 is mishandled ordropped.

In certain embodiments, the cap 138 also includes a tamper evident bandor tamper band 340. The tamper band 340 may be composed of abiocompatible polymer, and may be molded, cast, additive manufactured,etc. The tamper band 340 may be coupled to the cap 138 via a pluralityof bridges, which are breakable upon unscrewing or uncoupling the cap138 from the plunger 122. In this example, the plunger 122 also definesa tamper bead retaining catch 342 about an outer perimeter of theplunger 122. The tamper bead retaining catch 342 extends outward suchthat as the user is removing the cap 138, the tamper band 340 contactsthe tamper bead retaining catch 342. The contact between the tamper band340 and the tamper bead retaining catch 342, along with the continuedapplied force by the user, separates the cap 138 from the tamper band340 at the bridges, leaving the tamper band 340 about the plunger 122 tovisually indicate the cap 138 has been removed.

In certain embodiments, with reference to FIG. 4, in order to assemblethe disposable inserter 104, the needle carrier 160 is coupled to theinsertion needle 162. With the cartridge housing 154 formed, the thirdspring 152 is inserted into the cartridge housing 154. The needlecarrier 160 is inserted through the cartridge housing 154 such that theinsertion needle 162 is in the first, extended state (FIG. 7). Incertain embodiments, the lock arms 178 a, 178 b may be held duringassembly by an external force to maintain the insertion needle 162 inthe first, extended state. The cap 175 is coupled to the cartridgehousing 154. With reference to FIG. 13, the needle cartridge 120 isinserted into the retractor 128. The retaining arms 266 a, 226 b may beheld by an external force during assembly so that the retaining arms 266a, 266 b to apply a force F4 against the respective lock arms 178 a, 178b. The application of the force F4 by the retaining arms 266 a, 266 bcauses the lock arms 178 a, 178 b apply a force F5 to the needle carrier160, which maintains the insertion needle 162 in the first, extendedstate.

With reference to FIG. 3, with the retainer 132 coupled to the carrier134, the carrier 134 is coupled to the frame 126. The retraction spring130 is positioned within the second annular projection 256 of thecarrier 134. The retractor 128, including the needle cartridge 120, iscoupled to the second annular projection 256 of the carrier 134 so thatthe insertion needle 162 remains in the first, extended state. Theinsertion spring 124 is positioned within the first annular projection294 of the carrier 134. With the access cover 226 coupled to the accessopening 224, the plunger 122 is coupled to the frame 126. With referenceto FIG. 2, the physiological characteristic sensor 106 is coupled to thecarrier 134 so as to be retained by the retainer 132. The cap 138, withthe membrane 140 and the tamper band 340 coupled to the cap 138, isthreaded onto the plunger 122 and the frame 126. The cap 138 is coupledto the plunger 122 such that the projection 310 applies the force F3 tothe physiological characteristic sensor 106. The disposable inserter 104is in a first position in FIG. 2. The disposable inserter 104, includingthe physiological characteristic sensor 106, may be sterilized andshipped to an end user.

Once received, the user may remove the cap 138. As the user unscrews thecap 138, the tamper band 340 breaks along the bridges and remainscoupled to the plunger 122. With the cap 138 removed, the physiologicalcharacteristic sensor 106 is exposed for insertion. In addition, theremoval of the cap 138 removes the magnetic field generated by themagnet 136, which activates the physiological characteristic sensor 106to monitor the glucose sensor 114. The user may position the disposableinserter 104 at the desired insertion site, which may or may not bevisible to the user. The user may depress the plunger 122, which withreference to FIG. 14, releases the carrier 134 and the retainer arms 282of the retainer 132 (FIG. 14). The release of the carrier 134 and theretainer arms 282 separates the physiological characteristic sensor 106from the disposable inserter 104. Once the carrier 134 is released fromthe frame 126, the insertion spring 124 applies the force F1 to couplethe physiological characteristic sensor 106 to the user. As the sidewall256 a of the second annular projection 256 of the carrier 134 remainsadjacent to the retractor 128, the retaining arms 266 a, 266 b continueto apply the force F4 to the lock arms 178 a, 178 b of the cartridgehousing 154. The lock arms 178 a, 178 b, in turn, continue to apply theforce F5 to the needle carrier 160. Stated another way, as the sidewall256 a of the second annular projection 256 of the carrier 134 inhibitsthe outward deflection of the retaining arms 266 a, 266 b, the secondretaining arm end 270 of the retaining arms 266 a, 266 b applies theforce F4 to the second lock arm end 196 of the lock arms 178 a, 178 b,which in turn, applies the force F5 to the chamfered surfaces 170 of theneedle carrier 160. The application of the forces F4, F5 by theretractor 128 and the cartridge housing 154 of the needle cartridge 120,respectively, maintain the insertion needle 162 in the first, extendedstate during the deployment of the physiological characteristic sensor106 onto the anatomy. The disposable inserter 104 is in a secondposition in FIG. 14.

Generally, once the insertion spring 124 deploys the carrier 134 and thephysiological characteristic sensor 106 is coupled to the anatomy, theretraction spring 130 applies the force F2 and retracts the retractor128 upward toward the access opening 224. The movement of the retractor128 toward the access opening 224 directs or urges the needle cartridge120 toward the access opening 224. Once the retraction spring 130 hasmoved the retractor 128 past the sidewall 256 a of the carrier 134, aforce F7 of the third spring 152 is greater than a force applied by theretaining arms 266 a, 266 b and the lock arms 178 a, 178 b, as theretaining arms 266 a, 266 b and the lock arms 178 a, 178 b are able toexpand outwardly or deflect unrestrained by the carrier 134. The forceF7 applied as the third spring 152 expands moves the needle carrier 160,along with the insertion needle 162, toward the cap 175 of the cartridgehousing 154, thereby moving the insertion needle 162 to the second,retracted state as shown in FIG. 15. Stated another way, once theretractor 128 has moved past the sidewall 256 a, the retaining arms 266a, 266 b are released, which in turn releases the lock arms 178 a, 178b, which in turn, releases the needle carrier 160 such that the force F7of the third spring 152 may move the insertion needle 162 to the second,retracted state. In the second, retracted state, the insertion needle162 is wholly contained within the cartridge housing 154. In the second,retracted state, the second lock arm end 196 of the lock arms 178 a, 178b along with the third spring 152 inhibit the needle carrier 160 frommoving rearward or back into the first, extended state to therebyinhibit a potential inadvertent exposure of the insertion needle 162from the cartridge housing 154.

The continued application of the force F2 of the retraction spring 130moves the retractor 128, and thus, the needle cartridge 120 toward thefirst end 122 a of the plunger 122. When the access cover 226 isattached to the plunger 122 as shown in FIG. 15, the needle cartridge120 is biased by the retractor 128, via the retraction spring 130,toward the first end 122 a. Generally, as the needle cartridge 120extends a distance D10 (FIG. 14) beyond the retractor 128 whenassembled, the retraction spring 130 is not able to fully expand toposition the retractor 128 against a surface 123 of the plunger 122 atthe first end 122 a due to contact between the access cover 226 and thecap 175 of the cartridge 156. When the access cover 226 is removed, byplacing a finger in the recessed notch 234 and pulling the access cover226 (FIG. 15) away from the access opening 224, for example, theretraction spring 130 is able to fully expand, and the force F2 of theretraction spring 130 moves the retractor 128 toward the first end 122 aof the plunger 122 to seat the retractor 128 against the surface 123 (asshown in FIG. 17). As shown in FIG. 16, with the retraction spring 130fully expanded, the cap 175 and the first cartridge end 176 extendbeyond the surface 122 c of the plunger 122 at the first end 122 a,which enables the user to easily grasp and remove the needle cartridge120 from the disposable inserter 104 (FIG. 10).

With reference to FIG. 17, a cross-sectional view of the needlecartridge 120 removed from the disposable inserter 104 is shown. In FIG.17, the disposable inserter 104 is in a third position. In the thirdposition, the retraction spring 130 is fully extended such that theretractor 128 is coupled to the first inner guide surface 238 and ispositioned at the surface 123 at the first end 122 a. As the needlecartridge 120 is removed from the disposable inserter 104, thedisposable inserter 104 may be disposed of at the user's home or otherlocation via recycling for example. Thus, the disposable inserter 104does not require the user to dispose of the disposable inserter 104 in abiohazard and/or sharps container as the needle cartridge 120, whichcontains the insertion needle 162, has been removed from the disposableinserter 104. This provides convenience to the user, and enables theuser to install the physiological characteristic sensor 106 and disposeof the disposable inserter 104 conveniently in any recycling or garbagebin. The user may also easily dispose of the needle cartridge 120 uponremoval of the needle cartridge 120 from the disposable inserter 104.

It should be noted that while the disposable medical device introductionsystem 100 is described herein as being used to deploy the physiologicalcharacteristic sensor assembly 102, including the physiologicalcharacteristic sensor 106, on the anatomy, a disposable medical deviceintroduction system may be configured differently. In this regard, withreference to FIG. 18, a disposable medical device introduction system400 is shown. As the disposable medical device introduction system 400includes the same or similar components as the disposable medical deviceintroduction system 100 discussed with regard to FIGS. 1-17, the samereference numerals will be used. In this example, the disposable medicaldevice introduction system 400 includes an infusion unit assembly 402and a disposable inserter 404. In FIG. 18, the disposable inserter 404is shown in the second position, in which the disposable inserter 404 iscoupling a portion of the infusion unit assembly 402 to the anatomy.

The infusion unit assembly 402 may comprise any suitable infusion unitassociated with an infusion set for dispensing a fluid to a user for usewith the disposable inserter 404, and thus, the infusion unit assembly402 will not be discussed in great detail herein. In this example, withreference to FIG. 19, the infusion unit assembly 402 includes aninfusion hub 405, a tubing connector 406 and the adhesive patch 108.Generally, the infusion hub 405 and the disposable inserter 404 may bepackaged together for use by a consumer or user. The infusion hub 405and the tubing connector 406 cooperate to define a fluid flow path froma fluid reservoir of a fluid infusion device, such as an insulin pump,to a body of a user.

Briefly, the infusion hub 405 includes an inlet 410, a conduit 412 and acannula 414 (FIG. 18). The infusion hub 405 may also define a bore 416,which enables the insertion needle 162 to pass through to insert thecannula 414 into the anatomy. The bore 416 may be covered by a septum.The inlet 410 fluidly couples the infusion hub 405 to the tubingconnector 406 to define a fluid flow path between the infusion hub 405and the tubing connector 406. Generally, the infusion hub 405 iscomposed of a biocompatible polymer, and may be cast, printed, molded,etc. The inlet 410, the conduit 412 and the bore 416 may each beintegrally formed with the infusion hub 405, and the cannula 414 maycomprise a portion of flexible tubing, which is formed discretely andcoupled to the infusion hub 405 via ultrasonic welding, for example. Theinfusion hub 405 has a hub distance D12, which is different and lessthan a distance D13 of the tubing connector 406. The inlet 410 isdefined through a perimeter of the infusion hub 405 and is in fluidcommunication with the conduit 412. The conduit 412 extends radiallyfrom the inlet 410 to the bore 416. The conduit 412 defines a fluid flowpath from the inlet 410 to the bore 416. The bore 416 is defined axiallythough the infusion hub 405. The bore 416 enables the insertion needle162 to pass through the infusion hub 405 to couple the cannula 414 tothe anatomy, and also defines a fluid flow path between the conduit 412and the cannula 414. The cannula 414 extends axially along a centralaxis defined by the bore 416 (FIG. 18). The cannula defines a fluid flowpath from the infusion hub 405 to the anatomy (FIG. 18). The adhesivepatch 108 is coupled to the infusion hub 405 along a bottom surface 405a (FIG. 18) of the infusion hub 405.

The tubing connector 406 defines an inner bore 420, an inlet 422, atubing conduit 424 and an outlet 426. The inner bore 420 is sized tohave a distance D14, which is different and greater than the distanceD12 of the infusion hub 405, to enable the tubing connector 406 to bepositioned about the infusion hub 405 to fluidly couple the infusion hub405 to the tubing connector 406. The inlet 422 is defined through aperimeter of the tubing connector 406 and is in fluid communication withthe tubing conduit 424. The inlet 422 is fluidly coupled to a tubing428, which is a source of fluid for the infusion unit assembly 402.Generally, the tubing 428 is fluidly coupled to the fluid infusiondevice, such as an infusion pump, to receive a fluid, such as insulin.The tubing conduit 424 extends radially from the inlet 422 to the outlet426. The tubing conduit 424 defines a fluid flow path from the inlet 422to the outlet 426. When the tubing connector 406 is coupled to theinfusion hub 405, the outlet 426 is fluidly coupled to the inlet 410 ofthe infusion hub 405. In certain embodiments, the tubing 428 may extendthrough an opening defined through the tubing connector 406 such thatthe tubing 428 is the tubing conduit 424, which terminates at the outlet426.

With reference back to FIG. 18, in various embodiments, the infusion hub405 is coupled to the disposable inserter 404 for shipping anddelivering the infusion hub 405 to the user. The disposable inserter 404is manipulatable by a user to couple the cannula 414 and the infusionhub 405 to the user. The disposable inserter 404 includes the needlecartridge 120, the plunger 122, the insertion spring 124, the frame 126,the retractor 128, the retraction spring 130, the retainer 132, thecarrier 134 and the cap 138 (FIG. 2). The cap 138 includes the membrane140 (FIG. 2). In this example, the disposable inserter 404 is the sameas the disposable inserter 104, however, the cap 138 of disposableinserter 404 does not include the magnet 136. Thus, the disposableinserter 404 will not be discussed in great detail herein.

The infusion hub 405 is coupled to the carrier 134 and retained by theretainer 132. The disposable inserter 404, including the infusion hub405, may be sterilized and shipped to an end user. Once received, theuser may remove the cap 138 (FIG. 2). As the user unscrews the cap 138,the tamper band 340 breaks along the bridges and remains coupled to theplunger 122. With the cap 138 removed, the infusion hub 405 is exposedfor insertion. The user may position the disposable inserter 404 at thedesired insertion site, which may or may not be visible to the user. Theuser may depress the plunger 122, which releases the carrier 134 and theretainer arms 282 of the retainer 132. The release of the carrier 134and the retainer arms 282 separates the infusion hub 405 from thedisposable inserter 404. Once the carrier 134 is released from the frame126, the insertion spring 124 applies the force F1 to couple theinfusion hub 405 to the user. The insertion needle 162 is maintained inthe first, extended state during the deployment of the infusion hub 405onto the anatomy due to the forces F4, F5 applied to the needle carrier160 by the lock arms 178 a, 178 b and the retaining arms 266 a, 266 b,respectively.

Generally, once the insertion spring 124 deploys the carrier 134 and theinfusion hub 405 is coupled to the anatomy, the retraction spring 130applies the force F2 and retracts the retractor 128 upward toward theaccess opening 224. Once the retraction spring 130 has moved theretractor 128 past the sidewall 256 a of the carrier 134, the force F7of the third spring 152 is greater than a force applied by the retainingarms 266 a, 266 b and the lock arms 178 a, 178 b, as the retaining arms266 a, 266 b and the lock arms 178 a, 178 b are able to expand outwardlyor deflect unrestrained by the carrier 134. The force F7 applied as thethird spring 152 expands moves the needle carrier 160, along with theinsertion needle 162, toward the cap 175 of the cartridge housing 154,thereby moving the insertion needle 162 to the second, retracted state(FIG. 15). In the second, retracted state, the insertion needle 162 isfully contained within the cartridge housing 154.

The continued application of the force F2 of the retraction spring 130moves the retractor 128, and thus, the needle cartridge 120 toward thefirst end 122 a of the plunger 122. The access cover 226 is removed, andthe retraction spring 130 is able to fully expand, to move the retractor128 toward the first end 122 a of the plunger 122 to seat the retractor128 against the surface 123 (as shown in FIG. 17). With the retractionspring 130 fully expanded, the cap 175 and the first cartridge end 176extend beyond the surface 122 c of the plunger 122 at the first end 122a, which enables the user to easily grasp and remove the needlecartridge 120 from the disposable inserter 404. With reference to FIG.20, with the infusion hub 405 coupled to the anatomy by the disposableinserter 404, the tubing connector 406 may be coupled to the infusionhub 405 to define a fluid flow path through the tubing 428 to theanatomy of the user via the cannula 414. Generally, the fluid flow paththrough the tubing 428 is coupled to the cannula 414 of the infusion hub405 via the conduit 412. The tubing 428 may be fluidly coupled to thefluid reservoir of the fluid infusion device, such as an insulinreservoir of an insulin pump.

It should be noted that while the disposable medical device introductionsystem 100 is described herein as being used to deploy the physiologicalcharacteristic sensor assembly 102, including the physiologicalcharacteristic sensor 106, on the anatomy, a disposable medical deviceintroduction system may be configured differently. In this regard, withreference to FIG. 21, a disposable medical device introduction system600 is shown. As the disposable medical device introduction system 600includes the same or similar components as the disposable medical deviceintroduction system 100 discussed with regard to FIGS. 1-17, the samereference numerals will be used. In this example, the disposable medicaldevice introduction system 600 includes an infusion unit 602 and adisposable inserter 604. In FIG. 21, the disposable inserter 604 isshown in the second position, in which the disposable inserter 604 iscoupling the infusion unit 602 to the anatomy.

The infusion unit 602 may comprise any suitable infusion unit associatedwith an infusion set for dispensing a fluid to a user for use with thedisposable inserter 604, and thus, the infusion unit 602 will not bediscussed in great detail herein. Generally, the infusion unit 602 andthe disposable inserter 604 may be packaged together for use by aconsumer or user. The infusion unit 602 defines a fluid flow path from afluid infusion device, such as an insulin pump, to a body of a user. Inthis example, with reference to FIG. 22, the infusion unit 602 includesa hub 605 and the adhesive patch 108.

Briefly, the hub 605 includes an inlet 610, a conduit 612 and a cannula614 (FIG. 21). The hub 605 may also define a bore 616, which enables theinsertion needle 162 to pass through to insert the cannula 614 into theanatomy. The bore 616 may be covered by a septum. The inlet 610 fluidlycouples the hub 605 to a tubing 628 to define a fluid flow path betweenthe infusion unit 602 and the fluid infusion device. Generally, the hub605 is composed of a biocompatible polymer, and may be cast, printed,molded, etc. The inlet 610, the conduit 612 and the bore 616 may each beintegrally formed with the hub 605, and the cannula 614 may comprise aportion of flexible tubing, which is formed discretely and coupled tothe hub 605 via ultrasonic welding, for example. In certain embodiments,the tubing 628 may extend through the inlet 610 and the conduit 612 andexit through the bore 616 to define the cannula 614.

The inlet 610 is defined through a perimeter or circumference of the hub605 and is in fluid communication with the conduit 612. The inlet 610 isfluidly coupled to the tubing 628, which is a source of fluid for theinfusion unit 602. Generally, the tubing 628 is fluidly coupled to thefluid reservoir of the fluid infusion device, such as an infusion pump,to receive a fluid, such as insulin. The conduit 612 extends radiallyfrom the inlet 610 to the bore 616. The conduit 612 defines a fluid flowpath from the inlet 610 to the bore 616. The bore 616 is defined axiallythough the hub 605. The bore 616 enables the insertion needle 162 topass through the hub 605 to couple the cannula 614 to the anatomy, andalso defines a fluid flow path between the conduit 612 and the cannula614. The cannula 614 extends axially along a central axis defined by thebore 616 (FIG. 21). The cannula 614 defines a fluid flow path from theinfusion unit 602 to the anatomy (FIG. 21). The adhesive patch 108 iscoupled to the hub 605 along a bottom surface 605 a (FIG. 21) of the hub605.

With reference back to FIG. 21, in various embodiments, the infusionunit 602 is coupled to the disposable inserter 604 for shipping anddelivering the infusion unit 602 to the user. The disposable inserter604 is manipulatable by a user to couple the cannula 614 and theinfusion unit 602 to the user. The disposable inserter 604 includes theneedle cartridge 120, the plunger 122, the insertion spring 124, theframe 126, the retractor 128, the retraction spring 130, the retainer132 and the carrier 134. In this example, the disposable inserter 604 issubstantially the same as the disposable inserter 104, however, thedisposable inserter 604 does not include the magnet 136 or the cap 138,and a portion of the plunger 122, the frame 126, the carrier 134 and theretainer 132 are removed to accommodate the tubing 628 that extends fromthe hub 605. It should be noted that the plunger 122, the frame 126, thecarrier 134 and the retainer 133 may be modified differently toaccommodate the tubing 628 coupled to the infusion unit 602. Generally,the plunger 122, the frame 126, the carrier 134 and the retainer 133need material removed to accommodate the tubing 628 with a predeterminedamount of clearance about the tubing 628. As the components of thedisposable inserter 604 are substantially the same as the components ofthe disposable inserter 104 except for the removal of the portion of theplunger 122, the frame 126, the carrier 134 and the retainer 132 toaccommodate the tubing 628, the disposable inserter 604 will not bediscussed in great detail herein.

It should be noted that in certain examples, a pedestal or over coveringmay surround the cannula 614 and the insertion needle 162 duringshipping to inhibit accidental contact with the insertion needle 162and/or cannula 614. Also, it should be noted that while the disposableinserter 604 is described herein as not including the cap 138, incertain embodiments, the disposable inserter 604 may include a cap,similar to cap 138, that presses onto the plunger 122. In this example,the cap may include a projection, similar to the projection 310, tosupport the infusion unit 602 during shipping to the user. The press-oncap also includes clearance for the tubing 628, and may include a notchor other clearance formed about a perimeter of the cap to accommodatethe tubing 628.

Generally, the hub 605 is coupled to the carrier 134 and retained by theretainer 132. The disposable inserter 604, including the hub 605, may besterilized in suitable packaging and shipped to an end user. Oncereceived, the user may remove the disposable inserter 604 from thepackaging to expose the hub 608 for insertion. The user may position thedisposable inserter 604 at the desired insertion site, which may or maynot be visible to the user. The user may depress the plunger 122, whichreleases the carrier 134 and the retainer arms 282 of the retainer 132.The release of the carrier 134 and the retainer arms 282 separates thehub 605 from the disposable inserter 604. Once the carrier 134 isreleased from the frame 126, the insertion spring 124 applies the forceF1 to couple the hub 605 to the user. The insertion needle 162 ismaintained in the first, extended state during the deployment of the hub605 onto the anatomy due to the forces F4, F5 applied to the needlecarrier 160 by the lock arms 178 a, 178 b and the retaining arms 266 a,266 b, respectively.

Generally, once the insertion spring 124 deploys the carrier 134 and thehub 605 is coupled to the anatomy, the retraction spring 130 applies theforce F2 and retracts the retractor 128 upward toward the access opening224. Once the retraction spring 130 has moved the retractor 128 past thesidewall 256 a of the carrier 134, the force F7 of the third spring 152is greater than a force applied by the retaining arms 266 a, 266 b andthe lock arms 178 a, 178 b, as the retaining arms 266 a, 266 b and thelock arms 178 a, 178 b are able to expand outwardly or deflectunrestrained by the carrier 134. The force F7 applied as the thirdspring 152 expands moves the needle carrier 160, along with theinsertion needle 162, toward the cap 175 of the cartridge housing 154,thereby moving the insertion needle 162 to the second, retracted state(FIG. 15). In the second, retracted state, the insertion needle 162 isfully contained within the cartridge housing 154.

The continued application of the force F2 of the retraction spring 130moves the retractor 128, and thus, the needle cartridge 120 toward thefirst end 122 a of the plunger 122. The access cover 226 is removed, andthe retraction spring 130 is able to fully expand, to move the retractor128 toward the first end 122 a of the plunger 122 to seat the retractor128 against the surface 123 (as shown in FIG. 17). With the retractionspring 130 fully expanded, the cap 175 and the first cartridge end 176extend beyond the surface 122 c of the plunger 122 at the first end 122a, which enables the user to easily grasp and remove the needlecartridge 120 from the disposable inserter 604. With reference to FIG.23, with the infusion unit 602 coupled to the anatomy by the disposableinserter 604, the tubing 628 defines a fluid flow path to the anatomy ofthe user via the cannula 614. The fluid flow path through the tubing 628is fluidly coupled to the cannula 614 of the hub 605 via the conduit612. The tubing 628 may be fluidly coupled to the fluid reservoir of thefluid infusion device, such as an insulin reservoir of an insulin pump.

Thus, the disposable inserter 104, 404, 604, which includes the needlecartridge 120, enables the disposable inserter 104, 404, 604 to berecycled or otherwise disposed of easily by the user, without requiringdisposal in a biohazard and/or sharps container. In this regard, the useof the needle cartridge 120 to contain the insertion needle 162 afterinsertion of the glucose sensor 114 or cannula 414, 614, respectively,enables the biohazard (the insertion needle 162) to be removed from thedisposable inserter 104, 404, 604 for separate disposal, therebyenabling recycling of the disposable inserter 104, 404, 604. Therecycling of the disposable inserter 104, 404, 604 is environmentallyfriendly. Moreover, the easy disposal of the disposable inserter 104,404, 604 improves convenience for the user. In addition, the user mayeasily dispose of the needle cartridge 120 once removed from thedisposable inserter 104, 404, 604.

It should be understood that various aspects disclosed herein may becombined in different combinations than the combinations specificallypresented in the description and accompanying drawings. It should alsobe understood that, depending on the example, certain acts or events ofany of the processes or methods described herein may be performed in adifferent sequence, may be added, merged, or left out altogether (e.g.,all described acts or events may not be necessary to carry out thetechniques). In addition, while certain aspects of this disclosure aredescribed as being performed by a single module or unit for purposes ofclarity, it should be understood that the techniques of this disclosuremay be performed by a combination of units or modules associated with,for example, a medical device.

In addition, certain terminology may also be used in the followingdescription for the purpose of reference only, and thus are not intendedto be limiting. For example, terms such as “upper”, “lower”, “above”,and “below” refer to directions in the drawings to which reference ismade. Terms such as “front”, “back”, “rear”, “side”, “outboard”, and“inboard” describe the orientation and/or location of portions of thecomponent within a consistent but arbitrary frame of reference which ismade clear by reference to the text and the associated drawingsdescribing the component under discussion. Such terminology may includethe words specifically mentioned above, derivatives thereof, and wordsof similar import. Similarly, the terms “first”, “second”, and othersuch numerical terms referring to structures do not imply a sequence ororder unless clearly indicated by the context.

While at least one exemplary embodiment has been presented in theforegoing detailed description, it should be appreciated that a vastnumber of variations exist. It should also be appreciated that theexemplary embodiment or embodiments described herein are not intended tolimit the scope, applicability, or configuration of the claimed subjectmatter in any way. Rather, the foregoing detailed description willprovide those skilled in the art with a convenient road map forimplementing the described embodiment or embodiments. It should beunderstood that various changes can be made in the function andarrangement of elements without departing from the scope defined by theclaims, which includes known equivalents and foreseeable equivalents atthe time of filing this patent application.

What is claimed is:
 1. A disposable inserter for a medical device, comprising: a carrier to receive the medical device, the carrier comprising at least one annular projection; a retractor received within the at least one annular projection and movable relative to the at least one annular projection, the retractor having at least one retaining arm; and a needle cartridge coupled to the retractor that includes an insertion needle, and the at least one retaining arm cooperates with the needle cartridge to maintain the insertion needle in a first, extended state, and a movement of the retractor relative to the at least one annular projection releases the at least one retaining arm to move the insertion needle from the first, extended state to a second, retracted state.
 2. The disposable inserter of claim 1, wherein in the second, retracted state, the insertion needle is retained wholly within the needle cartridge.
 3. The disposable inserter of claim 1, wherein the retractor includes at least one internal slot and the needle cartridge includes a cartridge housing having at least one coupling tab that is slidably coupled to the at least one internal slot.
 4. The disposable inserter of claim 1, wherein the needle cartridge includes a cartridge housing that contains the insertion needle, and at least one lock arm is defined on the cartridge housing that cooperates with the at least one retaining arm to maintain the insertion needle in the first, extended state.
 5. The disposable inserter of claim 4, wherein the needle cartridge includes a needle carrier coupled to the insertion needle, and the at least one lock arm is configured to apply a force to the needle cartridge to maintain the insertion needle in the first, extended state.
 6. The disposable inserter of claim 5, wherein the needle carrier includes at least one contact surface, and the at least one lock arm includes a lock arm end with at least one first contact surface to apply the force to the at least one contact surface.
 7. The disposable inserter of claim 6, wherein the lock arm end of the at least one lock arm includes a second contact surface opposed from the at least one first contact surface, and the second contact surface is configured to contact a retaining arm end of the at least one retaining arm to maintain the insertion needle in the first, extended state.
 8. The disposable inserter of claim 5, wherein the needle cartridge further comprises a biasing member positioned between the needle carrier and an end of the cartridge housing, and in the first, extended state, the biasing member is compressed by the needle carrier.
 9. The disposable inserter of claim 8, wherein the movement of the retractor relative to the at least one annular projection releases the at least one lock arm to release the needle carrier to move the insertion needle to the second, retracted state by the biasing member.
 10. The disposable inserter of claim 1, further comprising: a plunger that defines an access opening and includes an access cover removably coupled to the access opening, wherein the needle cartridge is removable through the access opening.
 11. The disposable inserter of claim 10, wherein the movement of the retractor relative to the at least one annular projection is urges the needle cartridge toward the access opening.
 12. A disposable medical device introduction system, comprising: a medical device; and a disposable inserter, including: a plunger defining an access opening enclosed by a removable access cover; a carrier to receive the medical device, the carrier comprising at least one annular projection, wherein the carrier is movable relative to the plunger; a retractor received within the at least one annular projection and movable relative to the at least one annular projection, the retractor having at least one retaining arm; and a needle cartridge coupled to the retractor and comprising an insertion needle, and the at least one retaining arm cooperates with the needle cartridge to maintain the insertion needle in a first, extended state, a movement of the retractor relative to the at least one annular projection releases the at least one retaining arm to move the insertion needle from the first, extended state to a second, retracted state, and the needle cartridge is removable through the access opening.
 13. The disposable medical device introduction system of claim 12, wherein in the second, retracted state, the insertion needle is retained wholly within the needle cartridge.
 14. The disposable medical device introduction system of claim 12, wherein the retractor includes at least one internal slot and the needle cartridge includes a cartridge housing having at least one coupling tab that is slidably coupled to the at least one internal slot.
 15. The disposable medical device introduction system of claim 12, wherein the needle cartridge includes a cartridge housing that contains the insertion needle, and at least one lock arm is defined on the cartridge housing that cooperates with the at least one retaining arm to maintain the insertion needle in the first, extended state.
 16. The disposable medical device introduction system of claim 15, wherein the needle cartridge includes a needle carrier coupled to the insertion needle, and the at least one lock arm is configured to apply a force to the needle cartridge to maintain the insertion needle in the first, extended state.
 17. The disposable medical device introduction system of claim 16, wherein the needle cartridge further comprises a biasing member positioned between the needle carrier and an end of the cartridge housing, and in the first, extended state, the biasing member is compressed by the needle carrier.
 18. The disposable medical device introduction system of claim 17, wherein the movement of the retractor relative to the at least one annular projection releases the at least one lock arm to release the needle carrier to move the insertion needle to the second, retracted state by the biasing member.
 19. The disposable medical device introduction system of claim 12, wherein the movement of the retractor relative to the at least one annular projection urges the needle cartridge toward the access opening.
 20. The disposable medical device introduction system of claim 12, wherein the medical device is a physiological characteristic sensor, an infusion hub or an infusion unit. 